Solid-Phase Exchange Radioiodination of Aryl Iodides. Facilitation by Ammonium Sulfate

Article abstract of DOI:10.1021/jo00347a022

A mild and simple technique for the synthesis of aryl radioiodides of high specific activity involving a solid-phase exchange between no-carrier-added radioiodide and unactivated aryl iodides is described.Mildly acidic, oxidizing conditions, provided by the in situ thermal decomposition of ammonium sulfate, appear to be necessary for the success of the exchange.Typical isolated radiochemical yields of >70percent have been obtained for a variety of aryl iodides, including various aralkyl amines, guanidines, carboxylic acids, and amino acids.Specific activities of up to 100 Ci/mmol of our model compound, (m-<125I>iodobenzyl)guanidine, have been achieved.Preliminary experiments suggest that, with this technique, interhalogen exchange of aryl bromides with radioiodine is a feasible approach to the preparation of no-carrier-added aryl radioiodides.